install emacs 24.4 error on mint

Question

I followed this link . But got error, how to fix?

$ sudo apt-get build-dep emacs24
[sudo] password for oracle: 
Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to find a source package for emacs24

$ cat /etc/apt/sources.list
#deb cdrom:[Linux Mint 17 _Qiana_ - Release amd64 20140530]/ trusty contrib main non-free
  deb http://packages.linuxmint.com qiana main upstream import
           deb http://extra.linuxmint.com qiana main
           deb http://mirror.nexcess.net/ubuntu trusty main restricted universe multiverse
           deb http://mirror.nexcess.net/ubuntu trusty-updates main restricted universe multiverse
           deb http://security.ubuntu.com/ubuntu/ trusty-security main restricted universe multiverse
           deb http://archive.canonical.com/ubuntu/ trusty partner

Answer 1

Open the software-sources application, and click "Enable source code repositories"

Then try again.

Answer 2

This is from my recipe for Travis CI:

sudo add-apt-repository -y ppa:cassou/emacs
sudo apt-get update -qq
sudo apt-get install -qq emacs24

Might be useful.